Valve

ABSTRACT

A VALVE STRUCTURE INCLUDING A BODY AND A CONDUIT THERETO, THE BODY AND CONDUIT FORMING A VALVE CHAMBER, AND THE CONDUIT PROVIDING A VALVE SEAT WITH A PISTON-TYPE VALVE IN THE VALVE CHAMBER ENGAGEABLE WITH THE VALVE SEAT AND BEING SUPPORTED BY THE BODY BY MEANS OF AN ANNULAR SUPPORT ON THE BODY HAVING A STATIONARY EXTERNAL SEALING MEANS, THE PISTON VALVE HAVING A CYLINDRICAL SKIRT SURROUNDING THE ANNULAR SUPPORT ON THE VALVE BODY AND ENGAGEABLE WITH THE SEALING MEANS TO FORM A PRESSURE CHAMBER WITHIN THE PISTON VALVE AND ANNULAR SUPPORTING WALL ON THE BODY IN COMBINATION WITH MEANS WHEREBY PRESSURE OF THE FLUID IN THE CONDUIT WILL OPEN THE VALVE, AND FLUID PRESSURE WITHIN THE PRESSURE CHAMBER WHEN ADMITTED THERETO WILL FUNCTION TO CLOSE THE PISTON VALVE.

United States Patent [72] Inventor Arwon P. llardison 2,851,055 9/1958Mosher .I 137/400 Glendon, Calif. 3,155,108 11/1964 Kahn et a1 137/220pp 8711612 FOREIGN PATENTS [221 PM 1969 973 192 10/1964 Great BritainPatented June 28, 1971 [73] Assignee Schulz Tool and Manulacturing Co.Primary Examiner-Robe" Nelson San Gabriel, Calif. Attorney-Wham andMcManigal Continuation of application Ser. No. 656,641, July 26, 1967,now abandoned.

ABSTRACT: A valve structure including a body and a conduit [54] VALVEthereto, the body and conduit forming a valve chamber, and im 6 D theconduit providing a valve seat with a piston-type valve in [gs the valvechamber engageable with the valve seat and being [52] US. Cl 137/220,Supported by the body by means f an annuhr support on the 137/4001137/6142, 251/24 body having a stationary external sealing means, thepiston Ill!- 3131/34 valve having a cylindrical skirt surrounding theannular sup- Field of Search 137/219, port on the va|ve body andengageable with the Seahng means 614-21; 251/34, 44 to form a pressurechamber within the piston valve and annular supporting wall on the bodyin combination with means [56] References cued whereby pressure of thefluid in the conduit will open the UNITED STATES PATENTS valve, andfluid pressure within the pressure camber when ad- 2,085,893 7/ 1937Boland 137/219 mitted thereto will function to close the piston valve.

F 9/ 1 54 /4 5 k 2 55 Ix) 50 40 57 z@ 29 -575- 4 96 0 9 79 e7 97 J' W 06VALVE This application is a continuation of my copending applicationSer. No. 656,641, filed July 26, I967.

BACKGROUND OF INVENTION This invention pertains to the art of valves forpermitting the closing off of the flow of fluid or liquid through aconduit or from a conduit into a chamber.

In the prior art, valves are somewhat complicated in their constructionand are costly to manufacture and costly to repair. See, for example,the U.S. Pat. Ser. No. 2,851,055, issued Sept. 9, l958, to Mosher.

In the aircraft industry it is of great importance that valves bedependable in their functioning, form absolute closures, be light inweight, and easy to repair.

OBJECTS OF INVENTION It is an object of the present invention to providea valve simple in construction, light in weight, and reliable inoperation. In its preferred form the parts are welded together and thevalve is welded in the conduit in which it is used. The valve is of sucha low cost that the intent is that the valve not be repaired, but bereplaced by removing the used valve and welding in an entirely newvalve. The valve including these desirable points, involves uniquefeatures and principles which comprise the herein disclosed invention.

It is an object of my invention to provide a valve in which the conduitor conduits cooperate with the body of the valve to form the valvechamber and valve seat.

It is a further object of my invention to provide a valve as referred toin the preceding paragraph in which the supporting body includes thevarious seals and passages required in order that the conduit elementwhich cooperates with the body may be of very simple and readilyreplaceable construction.

It is an object of my invention to provide an arrangement as referred tohereinabove in which the piston valve of the valve structure has acylindrical skirt and is supported by an annular or cylindrical wallextending from the body, the annular wall extending within the skirt andthere being an annular seal engageable between the annular wall or skirtin order to form a pressure chamber within the piston valve.

It is another object of my invention to provide a simplified valvehaving the unique structural features referred to heretofore in whichthe conduit provides a conical valve seat and the piston valve elementprovides a spherical surface engageable with the valve seat incombination with bearing means for supporting the piston valve, thebearing means being located approximately at the center around which thespherical surface is generated.

It is mandatory that the valves do not leak, and, therefore, it ismandatory that the piston valve element will seat perfectly on its seatin order that an absolute closure will be effected. In the past it hasbeen necessary to make parts relatively heavy and of such designsstructurally that it will be assured that the valves will seatperfectly. It is an object of my present invention to provide anarrangement in which a piston valve will seat perfectly and it is anobject to accomplish this result by providing an arrangement in whichthe piston valve has a cylindrical bearing or guiding surface and inwhich there is a second bearing which is positioned to surround a pointaround which a spherical surface of the valve seating surface isgenerated.

It is a further object of my invention to provide a valve of the classdescribed in which the valve has a curved nose providing a semisphericalseating surface and also has a cylindrical skirt adapted to receive aninternal supporting seal which constitutes a sliding bearing arrangementfor the piston valve and in which there is a second relatively smalldiameter bearing surrounding the point around which the semisphericalseating surface is generated.

It is an object of my invention to provide a dual valve arrangement inwhich there is a body comprising the main supporting structure and towhich a pair of conduits are connected such as by welding, the pair ofconduits being belled or flared adjacent to their points of securementto the body in order to provide a valve chamber on each side of the bodyand a valve seat on each side of the body and in which there is a pistonvalve in each of the piston chambers operable to engage the valve seatsfor closing the valve or to be pressurally disengaged from the valveseats in order to open the valve and permit fluid to pass therethrough.

One form of my invention comprises a dual valve arrangement for aconduit adapted for use in a refueling system of an aircraft and inwhich the opening and closing of the valves is controlled by pilot meanspositioned in the fuel tank. This form of my invention includes thebroad and narrow aspects of it and will be used in this application as ameans for presenting the invention so that those skilled in the art maypractice the same.

Referring to the drawings:

FIG. 1 is a diagrammatic view illustrating the utility of the dual valvearrangement disclosed in detail herein;

FIG. 2 is a longitudinal sectional view through the dual valve of myinvention and through the conduit members which cooperate with otherparts to form the valve chambers and valve seats;

FIG. 3 is a view similar to FIG. 2 but with the piston valves in openposition;

FIG. 4 is a cross-sectional view taken on the line 4-4 of FIG.

FIG. 5 is a cross-sectional view taken on the line 5-5 of FIG. 2; and

FIG. 6 is a fragmentary sectional view taken on the line 6-6 of FIG. 5.

Referring to FIG. 1 of the drawings, 11 represents a fuel tank and 12represents a conduit by means of which fuel is introduced into the tank.In the form of my invention illustrated herein, the dual valvearrangement 14 of my invention is positioned in the fuel inlet conduitand is positioned within the fuel tank, Extending upwardly from thevalve are two pipes 14 and 16 which terminate near the upper part of thefuel tank and the open ends thereof are controlled; that is, permittedto be opened or closed by means of pilot valve arrangementsdiagrammatically illustrated. Each pilot valve arrangement includes apilot valve 17 engageable with a seat 18 to close the opening of eitherof the pipes 15 and 16. These pilot valves 17 are connected through link19 to floats 20, which floats are raised as the fluid level in the fueltank reaches the upper end of the fuel tank. The raising of the floatsmoves the pilot valves 17 into engagement with the seats 18 and thuscloses the pipes 15 and 16. By virtue of this operation both valves ofthe dual valve arrangement will be automatically closed in order thatfurther fuel will not be introduced into the fuel tank.

Referring to FIGS. 2 to 6, I will describe the details of constructionof a preferred form of my invention as disclosed herein. The numeral 25represents a body which, like other parts of the invention, with theexception of the seals, are preferably made of a light weight materialsuch as aluminum. The body 25 has a block section 26 and a pair ofcylindrical securing flanges 27 and 28 which are cylindrical, inalignment with each other, and project axially from the block 26 inopposite directions.

There is an inlet conduit 29 and an outlet conduit 30 which are enlargedor belled, as indicated at 3] and 32 respectively, the projecting endsof each enlargement or bell being fitted into counterbores 34 and 35 andwelded to the flanges 27 and 28, as shown, in order to form a firstvalve chamber 37 and a second valve chamber 38, the conical portions ofeach bell forming piston valve seats 39 and 40 respectively. Cylindricalor annular valve supporting walls or flanges 41 and 42 project axiallyfrom the block 26 of the body 25 in the pressure chambers 37 and 38respectively, and each of the cylindrical supports carry externalsealing means 43 and 44 respectively which consist of Teflon cups 45separated by spacers 46 and expanded by expanders 47.

Positioned in the-valve chamber 37 is a first piston valve 50 and in thevalve chamber 38 is a second piston valve 51. The term piston valve isnot used in a limited sense but is used because each valve has a nose 52and a cylindrical skirt or wall 53 which presents an open end toward theblock 26. The interior of each piston valve is hollow to provide a spacewhich, in connection with the space within the supports 41 and 42,provides a first pressure chamber 54 and a second pressure chamber 55.It will be noted that the supports 41 and 42 are surrounded by theskirts 53 and that the seals 43 and 44 engage inner cylindrical surfaces53a of the skirts to form a seal and, at the same time permittingmovement of the valves 50 and 51 between closed and open positions; andthey also constitute annular bearings for supporting the valves 50 and51. It will be noted that the seals 43 and 44 are positioned internallyof the skirts 53 and are thus protected from the main flow through thevalve, which flow is permitted from the chamber 37 to the chamber 38through passages 57. Each of the pistons 50 and 51 are provided withsemispherical seating faces 58 and 59 respectively, which are engageablewith the seats 39 and 40 when the valves are in closed position. Thesemispherical surfaces 58 and 59 are generated around prints 60 and 61respectively.

Extending axially into the pressure chambers 54 and 55 are first andsecond metering pin and bearing elements 62 and 63 respectively, whichcooperate with cylindrical bearing surfaces 64 and 65 respectively ofbosses 66 and 67, which project from the noses 52 of the piston valves50 and 51. These bearings are positioned around the points 60 and 61 andconstitute a second bearing surface for each of the piston valves whenthey are in closed position. This relationship of the bearing surfaces64 and 65 with the points 60 and 61 permit an adjustment to be made ifthere is any slight misalignment, this enabling the piston valves toproperly engage their seats.

Springs 69 and 70 are compressed between the block 26 and the noses ofthe valves in order to assert a force yieldably holding the pistonvalves 50 and 51 in closed positions when fluid or hydraulic forces arenot acting to otherwise position the valves.

Formed in the block 26 is a passage 71 as shown best in FIGS. and 6,which is connected to the first pressure chamber 54 and also to the pipe15, which extends to one of the pilot valves. When the pilot valve isopen, the passage 71 is open and fluid pressure, therefore, cannot bebuilt up within the pressure chamber 54.

Provided within the boss 66 and nose 52 ofthe valve 50 is a passage 75enlarged at 76 to receive a check valve 77, which is held against anannular seat 78 by means of a spring 79. The inner end of the passage 75is surrounded by the bearing surface 64 which receives the cylindricalend of the metering pin 62 which has formed in it a metering passage 80which is of reduced area of cross section near the end of the meteringpin as indicated at 81.

When fluid under pressure is introduced into the inlet conduit 29 aforce is exerted on the nose of the piston valve 50 and forces thisvalve into open position as shown in FIG. 3, in which position the endface 83 of the boss engages the stop 84 of the metering pin. It will benoted that the metering opening 80 extends into the stop 84 so that itis not obstructed when the annular face 83 engages the stop 84.

The piston valve 50 moves into open position because the pressure withinthe chamber 54 is less than the pressure of the fluid against the nose52. Because of the differential in these two pressures the check valve77 may move away from its seat and fluid may flow through the passage 75and the metering passage 80 into the first pressure chamber 54. However,in view of the fact that the pilot valves 17 are open the fuel can flowoutward through'the passage 71 and the pipe and the pressure within thechamber 54 will be maintained at a pressure less than the pressureagainst the nose.

The function of the check valve 77 is to prevent reverse flow and aresulting opening of the piston valve. If this is not a factor the checkvalve 77 may be eliminated.

Also formed within the block 26 is a passage 86 which is connected tothe chamber 37 through a port 87. This passage 86 is connected to thepipe 16 which extends to the top of the fuel tank and is controlled byone of the pilot valves 17. The passage is provided with a venturi 90 sothat when fluid is flowing through this passage in the directionindicated by the arrows 91, a vacuum or reduced pressure is applied tothe axial passage 92 which, in turn, is connected to a passage 93provided within and which extends to the end of the metering pin 63 inthe second pressure chamber 55. The boss 67 has a chamber of passage 94of which the opening within the hearing surface 65 forms a part. The endof the metering pin which extends through this bearing and into thepassage or chamber 94 has a metering passage 95 which is of reduced areaof cross section near the end ofthe metering pin, as indicated at 96.

When fuel is being introduced under pressure through the inlet conduit29 and the valve 50 has been unseated, the fuel will flow into thechamber 37 through the passages 57 and into the chamber 38. Also,because of the fact that the pilot valves 17 are open at this time, fuelwill flow through the port 87 through the passage 91 and through thepipe 16 into the upper part of the fuel tank. This produces a reducedpressure in the venturi which reduces the pressure in the secondpressure chamber 55. Because of the shape of the second valve member 51,and the various areas subjected to fluid pressure and acting indifferent directions, there will be a resulting force to overcome theforce of the spring 70 and the piston valve 51 will move into an openposition, at which time the end face 97 of the boss 67 will engage thestop 98. Communication to the passage 94 and 93 will not be interferedwith, however, because the metering opening is cut into the stop member98 as shown.

The piston valves 50 and 51 will remain in open position so long as fuelbeing supplied through the inlet conduit 29 and the passages through thepipes 15 and 16 are open. When the fuel level reaches the top of thetank, the floats 20 are raised and the pilot valves 17 are closed.

This causes the following operation with respect to the first pistonvalve 50. Closing of the passage 71 will cause the pressure within thepressure chamber 54 to substantially equal the pressure of the incomingfluid and since the areas exposed in a direction to close the valveexceeds those in the direction tending to open the valve, the valve 50,with the cooperation of the spring 69, will gradually move from theposition shown in FIG. 3 to the position shown in FIG. 2, the rate ofmovement of the valve 50 depending on the size of the metering passage80. As the piston approaches seating position the reduced area position81 of the metering passage becomes positioned within the bearing 64 andthe metering flow is reduced, thus causing the piston to move moreslowly as it approaches sealing position.

At the same time that this action just described is taking place theflow of fuel through the pipe 16 is stopped and the fuel, instead offlowing entirely through the passage 91, will flow through the firstportion thereof and then flow through the venturi opening 92 and thepassages 93, 94, 95 and 96 into the second pressure chamber 55, thuscausing the fuel pressure per square inch in the chamber to equal thefuel pressure per square inch around the chamber. Because of theproportioning of areas, which result in a force tending to close thevalve 51 being greater than those tending to open it, the valve 51 willmove toward closed position, and when the reduced area 96 of themetering passage 95 is within the bearing 65, the flow into the pressurechamber 55 will be reduced and closing movement of the valve will alsobe reduced as the valve approaches the seat.

When the tank filled and the valves 50 and 51, or either of them closed,the inlet conduit will be closed and may be disconnected from the sourceof supply. As fuel is used from the fuel tank the valves will remain inthese closed positions and will not leave these closed positions untilthe fuel supply is again connected to the inlet conduit 29 and fuelunder pressure supplied thereto as previously explained.

lclairn:

l. A valve comprising:

A. a body structure having a main flow passage means therethrough andhaving a pair of fixed annular valve supports extending outwardlytherefrom in opposite directions in axial alignment and each havingexternal annular sealing means supported thereby;

B. a pair of chamber forming elements, one being secured at each side ofsaid body structure and each forming a valve chamber and a valve seat;

C. a pair of piston valves sequentially arranged with respect to saidmain flow passage, one in each of said valve chambers, each of saidpiston valves being engageable with one of said seats and each of saidpiston valves having an annular skirt into which one of said annularsupports extend, the said sealing means on said annular supports formingseals with said annular skirts and permitting said piston valves to movebetween closed and opened positions, said annular valve supports andsaid piston valves cooperating to provide pressure chambers formed insaid skirts and said piston valves and positioned on each side of saidbody structure;

D. separate means providing a separate control fluid passage eachconnected to one of said pressure chambers whereby fluid under pressuremay be separately introduced into each of said pressure chambers whenfluid is supplied to the inlet of said valve, said upstream piston valvecontrolling the control fluid passage to the pressure chamber associatedwith the other of said piston valves;

E. and means operable to cause fluid pressure to build up in each ofsaid pressure chambers in order to cause each of said piston valves toengage oneof said seats.

